KR102727861B1 - variable tread apparatus by ball screw system of agricultural 4-wheel vehicle - Google Patents

Abstract

The present invention relates to a wheelbase variable device using a ball screw for an agricultural four-wheeled vehicle. The present invention can be usefully applied in a field where the wheelbase of an agricultural four-wheeled vehicle is to be varied simply and easily without worrying about overload or the like on the front wheels (130) and rear wheels (132) of the agricultural four-wheeled vehicle by rotating the front wheels (130) and rear wheels (132) of the agricultural four-wheeled vehicle 90 degrees in the wheelbase direction to change direction, and then the front wheels (130) and rear wheels (132) of the agricultural four-wheeled vehicle roll 90 degrees in the original driving direction to change direction.

Description

{Variable tread apparatus by ball screw system of agricultural 4-wheel vehicle}

The present invention relates to a wheelbase variable device using a ball screw of an agricultural four-wheeled vehicle, and more specifically, to a wheelbase variable device using a ball screw of an agricultural four-wheeled vehicle capable of varying the wheelbase of an agricultural four-wheeled vehicle according to the ridge width of a field so that the left and right wheels, which are the front and rear wheels of the agricultural four-wheeled vehicle, can stably drive along the furrows on both sides of the ridge.

An agricultural four-wheeled vehicle is a vehicle for transporting agricultural materials and crops by loading them in a loading compartment. It is a four-wheeled vehicle with two front wheels and two rear wheels installed on the left and right sides at the front and rear ends of the body frame, respectively, and a loading compartment installed on the body frame.

These agricultural four-wheel vehicles simply had the front and rear wheels installed on both ends of the body frame or axle, and only the left and right wheels of the front wheels were capable of turning, so there was no means of adjusting the width of the body frame or the wheel tread of the agricultural four-wheel vehicles.

Therefore, the ridge width is varied depending on the crop being cultivated, and if the wheelbase and ridge width of the agricultural four-wheeled vehicle do not match, one wheel must be positioned in the furrow between the ridges and the other wheel must be positioned above the ridge instead of the furrow between the ridges, or both wheels must be positioned above the ridges.

As above, when trying to drive an agricultural 4-wheel vehicle, there was a disadvantage in that the area was not solid and driving was impossible if there were crops planted in the furrows.

In addition, when driving with one wheel positioned in the furrow between the ridges and the other wheel positioned in the ridge that is not the furrow between the ridges, the ridges are higher than the furrows and their heights are not uniform, so the agricultural four-wheeled vehicle has no choice but to tilt to one side and wobble, which makes driving difficult and increases the possibility of a safety accident.

In order to reduce these existing problems, there was an urgent need for a wheelbase variable device that could appropriately adjust the wheelbase of agricultural four-wheel vehicles to suit the different ridge widths and various shapes of ridges depending on the crops cultivated in the field.

Based on the urgent need as mentioned above, an agricultural electric transport vehicle that can adjust the wheelbase of an agricultural vehicle is proposed and presented in the Republic of Korea Utility Model Publication No. 20-0108481 (hereinafter referred to as “Document 1”).

The agricultural electric transport vehicle of the above document 1 has two left and right wheels capable of rotating 360 degrees installed at the front of the body, and two left and right drive wheels with sprockets installed at the rear thereof, and the left and right drive wheels are equipped with a DC motor connected to a power source of a battery, and the left and right drive wheels are connected via a chain so that the pinion and gear of the DC motor mesh and are linked, and the body is formed symmetrically left and right, and a width-changing means is provided so that the width of the body can be varied by a fastening member.

The above-mentioned width variable means is provided with a connecting portion having a plurality of through holes formed at equal intervals in each body, and a connecting member having a plurality of through holes formed at equal intervals, so that the connecting portion and the connecting portion are connected by a fastening member by aligning the through holes of the connecting portion and the connecting member, and at the same time, the width of the body can be varied through the connecting portion and the connecting member.

Another variable width means is to provide a hollow housing-axle having a sprocket at the lower part of the body to rotate, and to fix a fixed-axle having a wheel on the housing-axle by moving it in the axial direction and fixing it with a fastening member, thereby varying the positions of the left and right wheels on both sides, thereby making it possible to achieve a wheel tread of the agricultural electric transport vehicle.

However, in the case of the agricultural electric transport vehicle of the above-mentioned document 1, whenever the wheelbase of the agricultural electric transport vehicle was to be adjusted according to the furrow width of the field, it was too cumbersome and difficult, and of course unreasonable, to move the body itself in the width direction of the body through the body's connecting part, connecting member, and fastening member.

In addition, whenever it was necessary to adjust the wheelbase of an agricultural electric transport vehicle by varying the positions of the left and right wheels on each side according to the furrow width of the field, the process of moving the fixed axle in the axial direction from each housing-axle provided at the bottom of the body and fixing it with a fastening member was too cumbersome, difficult, and unreasonable.

(Document 1) KR20-0108481 Y1 (Registered on 1997.08.22)

The purpose of the present invention is to solve the above-mentioned various problems and disadvantages of the conventional technology, and to provide a wheelbase variable device using a ball screw of an agricultural four-wheeled vehicle, which can vary the wheelbase of an agricultural four-wheeled vehicle by simultaneously bringing the left and right wheels of the agricultural four-wheeled vehicle close together and closing or spreading them apart to increase or decrease the gap between the left and right wheels on both sides, thereby positioning the left and right wheels of the agricultural four-wheeled vehicle in the furrows on both sides of the ridge according to the ridge width of the field, thereby allowing the left and right wheels of the agricultural four-wheeled vehicle to drive along the furrows that are relatively flat compared to the ridges, thereby enabling stable driving.

In addition, another purpose of the present invention is to provide a wheel tread variation device using a ball screw of an agricultural four-wheeled vehicle, which steers the left and right wheels of an agricultural four-wheeled vehicle in the wheel tread direction and then varies the wheel tread of the agricultural four-wheeled vehicle to match the ridge width of a field, thereby rolling the agricultural four-wheeled vehicle in the rolling direction of the left and right wheels during wheel tread variation, thereby minimizing frictional resistance between the ground of the field and the left and right wheels, thereby enabling wheel tread variation of the agricultural four-wheeled vehicle to be performed more easily.

In order to solve the above-described problem, the agricultural four-wheeled vehicle of the present invention comprises a loading compartment provided on a body frame, front wheels provided on both sides of the front end of the body frame, and rear wheels provided on both sides of the rear end, and a wheel tread variable means capable of varying the distance between the left and right wheels of the front and rear wheels, wherein the wheel tread variable means is provided at the center of the body frame between the left and right wheels forming the front and rear wheels, and is characterized by including a motor reducer capable of forward and reverse rotation, a pair of screw shafts extended toward the left and right wheels from the motor reducer and rotated by the motor reducer, and a nut member which is respectively connected to the pair of screw shafts, has left and right wheels, and moves in the longitudinal direction of the screw shaft according to the rotational direction of the screw shaft.

The above pair of screw shafts are provided as one screw shaft extending on both sides from the output rotation shaft of the motor reducer, and one screw shaft may be provided with a right-hand thread and the other screw shaft may be provided with a left-hand thread.

The above pair of screw shafts may be provided with one or a pair of ball screw units including nut members, and when provided with the above pair of ball screw units, the pair of ball screw units are connected to a motor reducer and a gear or coupling, etc., so as to be driven simultaneously, and the nut members fastened to the pair of screw shafts are driven to rotate so as to come closer to or move away from each other.

The left and right wheels on the above nut member may be provided with a steering means so that they can each turn (steer) in the nut member. The steering means is characterized by comprising: an upright housing provided upright on the nut member; a steering shaft rotatably installed in the upright housing and including one of the left and right wheels; and a steering motor reducer connected to the upper end of the steering shaft and configured to rotate the steering shaft.

A drive motor for directly driving the left and right wheels forming the front and rear wheels may be provided at the bottom of the above steering shaft. It is preferable that the drive motor be provided as an in-wheel motor in which the fixed axle is a stator and the outer outer shape thereof is a rotor.

The above nut member is mounted on a block of the LM guide to minimize movement with the body frame and to achieve stable linear movement when the screw shaft rotates. The LM guide is provided with a linear rail and a block that slides on the linear rail, and the nut member is mounted on the block of the LM guide.

According to the present invention, by using the screw shaft and nut member of the ball screw unit, the left and right wheels of the front and rear wheels of an agricultural four-wheeled vehicle are simultaneously folded or spread to increase or decrease the distance between the left and right wheels, thereby varying the wheel tread of the agricultural four-wheeled vehicle, and as a result, the left and right wheels of the agricultural four-wheeled vehicle can be positioned in the furrows on both sides of the furrow according to the ridge width of the field, so that the left and right wheels of the agricultural four-wheeled vehicle can run along the furrows that are relatively flat compared to the ridges, thereby providing the useful effect of enabling stable driving.

In addition, according to the present invention, by providing a steering shaft that is steered by a steering motor reducer on the left and right wheels forming the front and rear wheels of an agricultural four-wheeled vehicle, the wheel tread of the agricultural four-wheeled vehicle can be varied according to the ridge width of a field after steering in the wheel tread direction, and as a result, the wheel tread of the agricultural four-wheeled vehicle is varied while the left and right wheels roll in the rolling direction when the agricultural four-wheeled vehicle is wheeled, so that the frictional resistance between the ground of the field and the left and right wheels is minimized, and thus the wheel tread of the agricultural four-wheeled vehicle can be performed more easily.

FIG. 1 is a perspective view showing an agricultural four-wheeled vehicle to which a wheelbase variable device according to a preferred embodiment of the present invention is applied.
Figure 2 is a perspective view showing the state as viewed from the bottom of Figure 1.
Figure 3 is a perspective view showing only the wheel change device extracted from an agricultural four-wheel vehicle to which the wheel change device of the present invention is applied.
Figure 4 is a perspective view showing only the steering means extracted from Figure 3.
Figures 5 to 8 are drawings showing the wheel changing process of an agricultural four-wheel vehicle to which a wheel changing device according to the present invention is applied.

Hereinafter, the advantages and features of the present invention, and the method for achieving them will be apparent by referring to the embodiments described in detail below together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and the embodiments are provided only to make the disclosure of the present invention complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

FIGS. 1 to 8 are drawings illustrating an agricultural four-wheeled vehicle to which a wheelbase variable device according to a preferred embodiment of the present invention is applied.

As shown in the drawing, the agricultural four-wheeled vehicle according to the present invention is provided with a loading box (120) on a body frame (110), front wheels (130) are provided on both sides of the front end of the body frame (110), and rear wheels (132) are provided on both sides of the rear end, and is provided with a wheelbase variable means that varies the distance between the left and right wheels of the front wheels (130) and the rear wheels (132) as well as a steering means (150) for changing the direction of the wheels.

The above wheel tread variation means is provided with a front wheel tread variation means (140a) for varying the distance between the left and right wheels on both sides of the front wheel (130), and a rear wheel tread variation means (140b) for varying the distance between the left and right wheels on both sides of the rear wheel (132).

The above front wheel tread means (140a) is composed of a motor reducer (141) provided at the center of the lower surface of a body frame (110) between the left and right wheels forming the front wheel (130), a pair of screw axles (142, 143) extended from the motor reducer (141) toward the left and right wheels of the front wheel (130a), and a nut member (141, 145) which is each connected to the pair of screw axles (142, 143) and includes one wheel among the left and right wheels forming the front wheel (130) and is provided with a steering means (150) for changing the direction of the wheel.

It is preferable that the above motor reducer (141) adopt a step motor that can rotate in both directions and stops after rotating only as much as set by the rotation speed and rotation angle.

The above pair of screw shafts (142, 143) are concentrically installed on both sides of the motor reducer (141) and extend from the motor reducer (141) toward the left and right wheels of the front wheel (130), and are rotated in a forward and reverse direction according to the driving direction of the motor reducer (141).

It is preferable that one of the above-described pair of screw shafts (142, 143) is provided as a right-hand screw and the other is provided as a left-hand screw. This is because, when the pair of screw shafts (142, 143) are rotated in one direction, the nut members (144, 145) respectively fastened to the pair of screw shafts (142, 143) should come closer to each other or spread apart from each other. In addition, the above-described pair of screw shafts (142, 143) may be provided as the output rotation shaft of the motor reducer (141) itself. In other words, it may be provided as one screw shaft extending on both sides from the output rotation shaft of the motor reducer (141).

It is sufficient if the above nut members (144, 145) are each fastened to a pair of screw shafts (142, 143) and can move in the longitudinal direction of the screw shafts (142, 143) according to the rotational direction of the screw shafts (142, 143).

In addition, the nut member (144, 145) may be installed using an LM guide (146) to minimize movement with the body frame (110) and to ensure stable linear movement when the screw shaft (142, 143) is rotated and moved in its longitudinal direction. The LM guide (146) is provided to include a linear rail (146a) and a block (146b) that slides on the linear rail (146a), and the nut member (144, 145) may be mounted on the block (146b) of the LM guide (146).

When a nut member (144, 145) is fastened to the screw shaft (142, 143), it becomes a ball screw unit, and the ball screw unit can also be provided as a ball screw unit including a motor reducer (141) in the middle.

The above ball screw unit may be provided as a pair of two ball screw units each including one nut member on one screw shaft. In this case, when provided as a pair of ball screw units, the pair of ball screw units are connected to a motor reducer and a gear or coupling, etc., so that they are driven simultaneously. When the pair of screw shafts are rotated simultaneously, the nut members fastened to the pair of screw shafts are driven to rotate so as to come closer to or move away from each other.

The above steering means (150) is provided in the nut member (144, 145) and is intended to turn the left and right wheels forming the front wheel (130) in the wheel direction of the agricultural four-wheeled vehicle and then return them to their original positions. The nut member (144, 145) enables the left and right wheels to turn (steering) in the wheel direction, i.e., in a direction perpendicular to the driving direction, at 90 degrees.

The steering means (150) of the front wheel (130) is provided with an upright housing (151) installed vertically downward on a nut member (144, 145), a steering shaft (152) that is rotatably installed in the upright housing (151) and includes one of the left and right wheels, and a steering motor reducer (153) that is connected to the upper end of the steering shaft (152) and rotates the steering shaft (152) at a predetermined angle.

Since the above steering motor reducer (153) must be installed at the top of the upright housing (151), a mounting member such as a bracket may be provided on the nut member (144, 145) so as to have an installation space for the steering motor reducer (153) while allowing the upright housing (151) to be spaced downward.

It is preferable to adopt the above steering motor reducer (153) as a step motor that can rotate in both directions and stops after rotating only as much as set by the number of rotations and the angle of rotation. This is because it is sufficient to rotate the steering axle (152) of the left and right wheels 90 degrees, which is a direction perpendicular to the wheel travel direction of the left and right wheels, and then return it to its original position.

The steering means of the front wheel (130) described above is intended to minimize frictional resistance between the ground of the field and the left and right wheels when changing the wheelbase of an agricultural four-wheeled vehicle by rolling the left and right wheels in the rolling direction of the front wheels (130) without being dragged.

At the bottom of the above steering shaft (152), a driving motor (155) is provided to directly drive the front wheel (130). The driving motor (155) is provided as an in-wheel motor in which a horizontal fixed shaft is a stator and the outer outer shape thereof is a rotor. One of the left and right wheels forming the front wheel (130) is mounted on the rotor, which is the outer shape of the in-wheel motor (155). The driving motor (155) is provided as a motor capable of forward and reverse rotation to enable forward and backward movement.

The above rear wheel tread means (140b) has the same configuration as the front wheel tread means (140a), so its specific configuration will be omitted. The above tread variation device can selectively operate the front wheel tread means (140a) or the rear wheel tread means (140b), or simultaneously operate the front and rear wheel tread means (140a, 140b).

The wheel rotation process of an agricultural four-wheeled vehicle to which a wheel rotation device using a ball screw according to the present invention configured as described above is applied is briefly described.

First, the front wheels (130) and rear wheels (132) of an agricultural four-wheeled vehicle are each rotated 90 degrees in the wheel direction to change direction, and the front wheels (130) and rear wheels (132) roll closer or further apart by the distance desired for wheel rotation considering the width of a ridge or road, and then the front wheels (130) and rear wheels (132) of the agricultural four-wheeled vehicle are rotated 90 degrees in the original driving direction to change direction, thereby enabling wheel rotation of an agricultural four-wheeled vehicle to be performed simply and easily without worrying about overloading of the front wheels (130) and rear wheels (132) of the agricultural four-wheeled vehicle.

As described above, the process of changing the wheelbase of an agricultural four-wheeled vehicle will be described in detail. As shown in Fig. 5, the agricultural four-wheeled vehicle is in a state where the front wheels (130) and rear wheels (132) can move forward or backward, and the wheelbase, which is the distance between the left and right wheels forming the front wheels (130) and rear wheels (132) of the agricultural four-wheeled vehicle, is arranged at the widest interval.

In this way, when the steering motor reducer (153) forming the steering means of the front wheel (130) and the rear wheel (132) is operated once in a state where the wheels of the agricultural four-wheeled vehicle are arranged at the widest interval, the left and right wheels of the front wheel (130) and the rear wheel (132) rotate in the direction of the rotation arrow of FIG. 5, centered on the upright housing (151), together with the shaft-axle (152), in a direction perpendicular (90 degrees) to the driving direction, which is the wheel direction of the agricultural four-wheeled vehicle, and then stop in a state as shown in FIG. 6. In other words, the left and right wheels of the front wheel (130) and the rear wheel (132) are steered in the wheel direction of the agricultural four-wheeled vehicle, thereby effecting a change in direction.

In this state, when the motor reducer (141) installed between the left and right wheels of the front wheel (130) and the rear wheel (132) forming the front and rear wheel tread means (140a, 140b) is operated for a predetermined period of time, the screw shafts (142, 143) on both sides connected to the motor reducer (141) are rotated for a predetermined period of time, and as a result, the front wheel (130) and the rear wheel (132) including the steering means are moved together with the nut members (144, 145) fastened to the screw shafts (142, 143) on both sides.

In this way, when the front wheel (130) and the rear wheel (132) are moved together with the nut members (144, 145), the left and right wheels forming the front wheel (130) and the rear wheel (132) are turned in the wheel rotation direction, so that they roll in the rolling direction of the left and right wheels, and as a result, the movement is performed in a state where the frictional resistance between the ground of the field and the left and right wheels is minimized.

At this time, since one side of the pair of screw shafts (142, 143) is provided as a right-hand screw and the other side is provided as a left-hand screw, as the pair of screw shafts (142, 143) rotates in one direction, the nut members (144, 145) fastened to the pair of screw shafts (142, 143) move closer to each other in the direction of the straight arrows of Fig. 7. In this way, as the left and right wheels of the front wheel (130) and the rear wheel (132) come closer together with the nut members (144, 145) as shown in Fig. 7, they move to the wheelbase variable position of the agricultural four-wheel vehicle.

As shown above, when the left and right wheels of the front wheel (130) and the rear wheel (132) are moved to the wheel rotation variable position as shown in FIG. 7, and the steering motor reducer (153) forming the steering means of the front wheel (130) and the rear wheel (132) is operated again, the left and right wheels of the front wheel (130) and the rear wheel (132) are rotated in the direction of the rotation arrow of FIG. 7, centered on the upright housing (151), together with the shaft (152), in the direction perpendicular (90 degrees) to the wheel rotation direction, which is the driving direction of the agricultural four-wheel vehicle, and then stopped as shown in FIG. 8.

In other words, the left and right wheels of the front wheel (130) and the rear wheel (132) are turned in the driving direction of the agricultural four-wheel vehicle, thereby completing the wheel tread change of the agricultural four-wheel vehicle to a reduced interval as desired by the driver.

Conversely, in the case where the wheelbase of an agricultural four-wheeled vehicle is reduced and the driver wishes to widen or further reduce it, the driver can easily and conveniently achieve any desired wheelbase by sequentially operating as described above.

Although the preferred embodiments of the present invention have been shown and described above, the present invention is not limited to the specific embodiments described above, and various modifications may be made by those skilled in the art without departing from the gist of the present invention as claimed in the claims. Furthermore, such modifications should not be individually understood from the technical idea or prospect of the present invention.

110: Body frame 120: Loading box
130: Front wheel 132: Rear wheel
140a: Front wheel drive vehicle 140b: Rear wheel drive vehicle
141: Motor reducer 142,143: Screw shaft
144,145: Nutless 146: LM Guide
151: Upright housing 152: Steering-axis
153: Steering motor reducer

Claims (5)

A loading compartment is provided on the body frame, front wheels are provided on both sides of the front end of the body frame, and rear wheels are provided on both sides of the rear end of the body frame, and a wheelbase variable means is included to vary the distance between the left and right wheels of the front and rear wheels.
The above wheel travel variable means includes a motor reducer which is respectively provided in the center of the body frame between the left and right wheels forming the front and rear wheels and which is capable of rotating in the forward and reverse directions, a pair of screw shafts which are extended toward the left and right wheels from the motor reducer and rotated in the forward and reverse directions by the motor reducer, and a nut member which is respectively connected to the pair of screw shafts and is provided with left and right wheels and moves in the longitudinal direction of the screw shaft according to the rotational direction of the screw shaft.
A wheel tread variation device using a ball screw of an agricultural four-wheeled vehicle, characterized in that the left and right wheels on the nut member are provided with steering means for performing direction change (steering) and wheel tread variation on the nut member, and the steering means comprises: an upright housing provided upright on the nut member; a steering shaft rotatably installed in the upright housing and including one of the left and right wheels at the bottom; and a steering motor reducer connected to the upper end of the steering shaft and for rotating the steering shaft. In the first paragraph,
A wheelbase variable device using a ball screw for an agricultural four-wheeled vehicle, characterized in that the above pair of screw shafts are provided as one screw shaft extending to both sides from the output rotation shaft of the motor reducer, and one screw shaft is provided with a right-hand screw and the other screw shaft is provided with a left-hand screw. delete delete In the first paragraph,
A wheelbase variable device using a ball screw for an agricultural four-wheeled vehicle, characterized in that a drive motor is provided at the bottom of the steering shaft to directly drive the left and right wheels forming the front and rear wheels.

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